[PATCH V2 1/3] net: ethernet: ti: netcp: Handle both ERR_PTR and NULL from knav_dma_open_channel

[Nishanth Menon <nm@ti.com>]

The knav_dma_open_channel function has inconsistent return behavior: the
header returns NULL when the driver is disabled, while the driver
implementation returns ERR_PTR(-EINVAL). This inconsistency creates
confusion for callers.

Prepare for standardizing the function to return NULL by updating callers
to handle both ERR_PTR and NULL return values using IS_ERR_OR_NULL()
checks.

Suggested-by: Simon Horman <horms@kernel.org>
Signed-off-by: Nishanth Menon <nm@ti.com>
---
Changes in V2:
* renewed version

 drivers/net/ethernet/ti/netcp_core.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/ti/netcp_core.c b/drivers/net/ethernet/ti/netcp_core.c
index 857820657bac..2f9d26c791e3 100644
--- a/drivers/net/ethernet/ti/netcp_core.c
+++ b/drivers/net/ethernet/ti/netcp_core.c
@@ -1338,10 +1338,10 @@ int netcp_txpipe_open(struct netcp_tx_pipe *tx_pipe)
 
 	tx_pipe->dma_channel = knav_dma_open_channel(dev,
 				tx_pipe->dma_chan_name, &config);
-	if (IS_ERR(tx_pipe->dma_channel)) {
+	if (IS_ERR_OR_NULL(tx_pipe->dma_channel)) {
 		dev_err(dev, "failed opening tx chan(%s)\n",
 			tx_pipe->dma_chan_name);
-		ret = PTR_ERR(tx_pipe->dma_channel);
+		ret = -EINVAL;
 		goto err;
 	}
 
@@ -1678,10 +1678,10 @@ static int netcp_setup_navigator_resources(struct net_device *ndev)
 
 	netcp->rx_channel = knav_dma_open_channel(netcp->netcp_device->device,
 					netcp->dma_chan_name, &config);
-	if (IS_ERR(netcp->rx_channel)) {
+	if (IS_ERR_OR_NULL(netcp->rx_channel)) {
 		dev_err(netcp->ndev_dev, "failed opening rx chan(%s\n",
 			netcp->dma_chan_name);
-		ret = PTR_ERR(netcp->rx_channel);
+		ret = -EINVAL;
 		goto fail;
 	}
 
-- 
2.47.0